Can you mix bleach and ammonia?
If the two have already been mixed: leave the room, open windows and doors from outside if you can reach them without breathing the air, and ring your national poison line. Do not go back in to neutralise it — adding a third chemical to a reaction in progress is the intuitive move and the wrong one, and most exposures happen to the person who returns to clear it up.
What actually happens
Sodium hypochlorite and ammonia react to form chloramine vapours, which attack the eyes, throat and lungs. Low exposure causes coughing, watering eyes and chest tightness; heavier exposure in an enclosed space causes fluid to accumulate in the lungs, which can develop hours after the person feels better and has proved fatal. A small bathroom with the door shut is the worst possible room for it and the room where it usually happens.
How people end up doing it
Almost never on purpose. Glass cleaners and many all-purpose sprays contain ammonia and do not always say so prominently, so the reaction happens when someone uses two products in sequence on the same surface. Cat urine and cat litter are also ammonia sources, which is why bleaching a litter tray is a known route.
What to do instead
Pick one product and rinse thoroughly before using another. If the two have already met: leave the room, open windows and doors from outside if you can do it without breathing the air, and ring your national poison line. Do not go back in to neutralise it.
Cleaning products
| Combination | Verdict | Why |
|---|---|---|
| Bleach and vinegar | Toxic gas | No. Any acid plus bleach releases chlorine gas. |
| Baking soda and vinegar | Pointless | Safe, dramatic, and it leaves you with salt water. |
| Bleach and toilet cleaner | Toxic gas | No. Most toilet cleaners are acidic, so this is the bleach-and-acid reaction. |
| Bleach and rubbing alcohol | Toxic gas | No. It produces chloroform and other chlorinated compounds. |
| Hydrogen peroxide and vinegar | Do not | No — mixed in a bottle it forms peracetic acid, which is corrosive. |
| One drain cleaner and a different drain cleaner | Toxic gas | No. Drain cleaners come in strongly acidic and strongly caustic types, and combining them is violent. |
| Bleach and hydrogen peroxide | Do not | No — it is exothermic and destroys both, and can spray hot liquid. |
| Vinegar and castile soap | Pointless | Safe, and it curdles into a white mess that is worse than either. |
| Vinegar and ammonia | Pointless | Not dangerous, and they cancel each other out. |
Common questions
- Can you mix bleach and ammonia?
- No — this one produces a toxic gas. No. This is the classic household poisoning and it produces chloramine gas.
- What happens if you do?
- Sodium hypochlorite and ammonia react to form chloramine vapours, which attack the eyes, throat and lungs. Low exposure causes coughing, watering eyes and chest tightness; heavier exposure in an enclosed space causes fluid to accumulate in the lungs, which can develop hours after the person feels better and has proved fatal. A small bathroom with the door shut is the worst possible room for it and the room where it usually happens.
- What should I do instead?
- Pick one product and rinse thoroughly before using another. If the two have already met: leave the room, open windows and doors from outside if you can do it without breathing the air, and ring your national poison line. Do not go back in to neutralise it.
- What if I have already mixed them?
- Leave the room, ventilate it from outside, and ring your national poison line. Do not go back in to neutralise it.
Related pages
- Bleach and vinegar No — this one produces a toxic gas
- Baking soda and vinegar You can, but it achieves nothing
- Bleach and toilet cleaner No — this one produces a toxic gas
- Bleach and rubbing alcohol No — this one produces a toxic gas
- Hydrogen peroxide and vinegar No — it damages something or fails
- One drain cleaner and a different drain cleaner No — this one produces a toxic gas
- Bleach and vinegar Also produces a toxic gas
- Bleach and toilet cleaner Also produces a toxic gas
- Bleach and rubbing alcohol Also produces a toxic gas
- One drain cleaner and a different drain cleaner Also produces a toxic gas
- Hazard symbols What the pictogram on the bottle actually requires
Sources
- What Noises Cause Hearing Loss? — Centers for Disease Control and Prevention (Public domain (US Government))
- Occupational Noise Exposure — Occupational Safety and Health Administration (Public domain (US Government))